【作者】 吴秀英；

【导师】 李从信；

【作者基本信息】 大庆石油学院 ， 计算机软件与理论， 2008， 硕士

【摘要】 复杂场景的优化处理技术是解决场景的复杂性和交互实时性矛盾的有效手段,也是虚拟现实技术中的关键技术之一。虚拟现实技术是以图、文、声为基础进行场景的表现,所以本文首先简要介绍了计算机图形学的基本理论,包括:图形的表示方法、表示图形的数据准备以及图形的显示。在此基础上,介绍了优化场景的几何剖分技术,最常用的几何剖分技术有BSP树、四叉树、八叉树。这些为后期的应用研究奠定了坚实的理论基础。在模型的优化方面,着重讨论了多分辨率模型的简化算法,并对多分辨率模型简化的不同算法进行了划分归类,总结了不同算法的优缺点并进行了比较,对多分辨率模型简化的选择尺度、平滑过渡和误差度量准则这几方面做了详细的论述。递进网格在模型的简化上具有很重要的地位,本文介绍了递进网格的快速生成算法、基于边折叠的网格简化算法以及三角形折叠简化算法。在三维场景的绘制上主要介绍了场景的可见性剔除技术、入口技术、基于图像的加速绘制技术及场景的调度算法。最后以联合站虚拟培训系统为例,将多分辨率模型的平滑过渡、三角形折叠简化算法、入口技术以及场景调度等多种优化方法应用到系统中,提高了联合站虚拟培训系统的运行速度,并在应用中针对三角形折叠简化算法和场景调度策略的缺点进行了改进。更多还原

【Abstract】 Optimization technique of complex scene is an effective means for solving the contradiction of complexity and real-time interaction, and it also is one of the key techniques of virtual reality.Virtual reality technique displays the scene based on the graphics, text, and sound. So, this paper introduces the basic theory of computer graphics, including the methods of graphical displaying, the data preparation of graphics displaying and the graphics showing. On the basis of these, the paper introduces the spatial partition technology of the scene optimizing. The techniques used most commonly include BSP tree, quadtree and octree. All of these lay a solid theoretical foundation for the latter part of applied research. In the aspect of the model optimizing, different simplified algorithms of multiple levels of detail model are discussed emphatically and classified. The advantages and disadvantages of different methods are compared, and choosing scale, smooth transition and error metrics of multiple levels of detail model are discussed in detail. Progressive mesh is very important in the model simplification. This paper introduces the rapid generation algorithms of progressive mesh, edge collapsed algorithms of progressive mesh and the folded triangle simplified algorithm.On the drawing of 3D scenes, the scene visibility removed technology, portal technology, accelerated rendering technology basing image and scene scheduling algorithm are researched emphatically. Finally, all kinds of optimization methods that multi-resolution model of smooth transition, triangle folding simplified algorithm, portal technique, and scene scheduling are applied to the system basing on the joint station, which improve the system’s operating, and the simplified algorithm for folding triangle scene and the shortcomings of scheduling strategy are improved in this application.更多还原